TV review: Endeavour (ITV) offered a tantalising glimpse of the man behind the mask.​Endeavour treads such familiar ground, echoing the sleuthing spires of Lewis and, of course, Inspector Morse, that you might suspect it would struggle to carve its own identity. Yet, though last night was only the second episode, more than a year since its pilot, it instantly feels like a classic addition to the detective genre.

It might be a stretch to make the genetic connection between Shaun Evans and John Thaw, the bookends of Morse’s life, but there’s something in Evans’s distracted introversion as Morse the younger that connects to Morse the elder. The sense that life will inevitably turn out to be vaguely disappointing, saved only by personal infatuations, is already tapping out as a coda on Morse’s shoulder.

The format is familiar to the detective genre, last night’s murder spree culminating in the device of having the ingenious sleuth – Morse – unravel the seemingly disparate clues, much to the consternation of those who had doubted him throughout. But it was such a clever denouement, involving hymn numbers, the Periodic Table and crossword clues, that it felt surprisingly fresh. There were strong hints of Morse’s fractured childhood littered throughout, his impassioned championing of a young mother’s battle to get her son back – her family had taken him from her on the grounds that she was unfit – being a case in point.

His boss DI Thursday, played with indulgent aplomb by Roger Allam, was worried that Morse was letting his heart rule his head. ‘There’s a child in the middle of this being kept from its mother – if that’s a blind spot, then so be it,’ declared Morse, offering a rare glimpse of the man behind the mask. It made you want to see more.